We first saw the Milwaukee 9.0 Ah battery (48-11-1890) at the Milwaukee New Products Symposium in 2015, and immediately started wondering what kind of cordless tools this capacity could open up. They've pushed the envelope with cordless magnetic drills and rotary hammers. The Milwaukee 9Ah battery opens the final door for 18V table and miter saws.
What is the working capacity of the Milwaukee 9.0 Ah battery?
These Milwaukee 9 Ah batteries provide more than twice the work capacity of 5.0 Ah batteries because they can run cooler and more efficiently. To give you an idea of how this translates to real world applications, it can cut 258 times 2×10. In comparison, Hilti's 36V circular saw made 173 cuts. If 2x4s are your mainstay, then be aware that a single Milwaukee 9.0 Ah battery can make 537 cuts – that's an astronomical number and could take a full day's work. In fact, at a 2014 Milwaukee media event they bragged about the new Milwaukee FUEL M18 circular saw making 233 2×4 cuts. Times; they are changing.
Watt hours matter
If you want to do the math, the Milwaukee 9.0 Ah High Demand Battery delivers 162 Wh (watt hours), or energy. That's 80% more than the 90 Wh available on their 5.0 Ah battery pack. On a battery platform, more watt-hours means more runtime for you. It could also mean more power for you.
By the way, we found it very interesting that the results of our cordless circular saw review numbers matched to within 5% of the numbers Milwaukee used at their event showing how competing products from various manufacturers perform time and cutting power. If you're wondering if manufacturers tend to "stack decks", our experience is that most (not all!) are fairly reasonable and fair in their general statements.
More than 2x the power, but not twice the original
So how do you get twice as much work out of a 9.0 Ah battery pack as a 5.0 Ah battery? First you have to understand energy flow. The Milwaukee 9.0 Ah battery is more efficient thanks to the wide channel that supplies the voltage to the battery. They also run cooler. A cooler bag can get more done because it doesn't have to worry about overheating as easily.
The Milwaukee-designed RedLithium High Demand 9.0 Ah battery pack has five cells arranged in three staggered rows to distribute power in a way that keeps the pack compact—it's only slightly larger than a 4.0 or 5.0 Ah pack. They also retain all the features of the current Milwaukee M18 RedLithium batteries such as shock absorption, temperature control, RedLink electronics and water protection.
When to Use a 9Ah Battery
I knew the future of tools lay in cordless technology, but I didn't think we'd get this far so quickly. With the Milwaukee High Demand 9.0 Ah RedLithium Battery, you open up new possibilities. These new possibilities include a cordless SDS Max hammer drill, 24/7 runtime, a cordless saw that competes with corded models—and there are probably many more we haven't thought of yet.
You don't want to run these batteries on a tool that doesn't need them — no need to add extra weight (in ounces, but still). The Milwaukee 9.0 Ah battery is best suited for demanding tools and applications where you really need to squeeze the most power or runtime out of your cordless tool.
Milwaukee issued a press release reminding users that highly conductive and corrosive fluids can have disastrous consequences for your battery. Liquids such as bleach, salt water, and a host of other chemicals can create connections between batteries and cause them to fail. In its most spectacular form, this can cause the battery to smoke or catch fire.
With hoverboards and smartphones making the news with actual battery failures, it's a good reminder of how responsive these battery packs can be — if they're mishandled or poorly constructed. There's nothing wrong with the construction of a Milwaukee backpack, but if you're not careful with it, it can have serious consequences.
Why is the warning attached to the Milwaukee M18 high demand 9.0 Ah battery?
When we spoke to the masters in Milwaukee, they used a rather simple but clever word picture to help us understand why this was only just becoming a focus of their education.
Get two ladders – one with a working height of 3 feet and the other with a working height of 10 feet. Which would do more damage if you fell from it?
Certainly a higher ladder. This is a similar idea to the Milwaukee M18 High Demand 9.0 AH Battery. The increase in overall energy storage is much greater, and failures can be more dangerous. So, just like when you work at high altitudes, extra precautions need to be taken.
But like I said, the warnings are the same for all Li-ion batteries, it's just that there's a greater emphasis on educating end users as they get more powerful. It's always a good idea to avoid getting any fluids in your battery pack, but some fluids are worse than others.
Milwaukee 9.0 Ah Battery Characteristics
- Model: 48-11-1890
- Up to 5x increase in run time
- Up to 35% more power
- Run cooler up to 60%
- Up to 2x the performance of M18 Redlithium XC5.0
- Delivers more work per charge than any 18V battery on the market
- Beyond the performance of higher voltage or multi-cell platforms
- Fits all M18 tools
- Price: $199